Jump to content


Photo

Exposure


  • Please log in to reply
10 replies to this topic

#1 Jed Shepherd

Jed Shepherd
  • Basic Members
  • PipPip
  • 60 posts
  • Student

Posted 01 February 2011 - 11:56 PM

I own a 60D so im asking in regard to it but im sure the answer will apply to all of the canon dslr's. My question is about getting the best exposure out of the camera. Im wondering what would be the best option; letting highlights clip to some extent so that the rest of the image is exposed well or closing the iris to stop highlight clipping but darkening everything else. Im asking this as a kind of two part question. Im thinking in terms of color correction in post. By letting the highlights clip im losing the information for that section of the image but if i let them expose correclty then play with the shadows and midtones in post to brighten the areas which have become darker, would i get a reasonable image? I cant test this at the moment(macbook pro battery died) so im using a machine with no editing software.

I was thinking about this in terms of making it look like the camera has better dynamic range then it really does. Im using a low contrast picture style (not superflat, just low contrast, sharpness etc) so in theory i should get the most information within my shadows, so i was wondering if anyone had mucked around with getting really good exposure using a 3 way color corrector for example? Im sort of struggling to explain what i mean exactly but hopefully someone might be able to give me an answer and i can maybe build on my question from there.

Thanks

P.S. I know i could use a polarising filter to help with overexposed sky etc but im just refering to hot spots that appear within an evironment where a polarised filter wouldnt be ideal.
  • 0

#2 Jed Shepherd

Jed Shepherd
  • Basic Members
  • PipPip
  • 60 posts
  • Student

Posted 02 February 2011 - 03:37 AM

Thought i would add that i mean only closing the iris just enough to stop clipping or minimize clipping as much as possible. Im not talking extremes, just minute adjustment to get the best exposure.
  • 0

#3 Hal Smith

Hal Smith
  • Sustaining Members
  • 2280 posts
  • Cinematographer
  • OKC area

Posted 02 February 2011 - 05:12 AM

The quickest way to get an image to scream VIDEO is to clip the highlights. If you want the dark areas to read, put some light in them.
  • 0

#4 Jed Shepherd

Jed Shepherd
  • Basic Members
  • PipPip
  • 60 posts
  • Student

Posted 02 February 2011 - 05:41 AM

Thats why i was asking. Best way to not have hightlights clipping. For the sake of this question lets say within a shot that has to be available light only. A place where i cant light darker areas but may have blaring sun hitting some items within the frame. Was wondering if it would be best to get good exposure on the highlights and then try and boost the underexposed areas or to just try and find the best balance and not think about a post correction? My common sense says to do the latter but i was just wondering if anyone had tried to brighten an underexposed image without experiencing too many artefacts on dslr footage.

Just thinking about the best way to get cinematic footage and i thought that having an image which appears to have good dynamic range, so no highlight clipping would be a good place to start.
  • 0

#5 K Borowski

K Borowski
  • Basic Members
  • PipPipPipPip
  • 3905 posts
  • Camera Operator
  • I.A.T.S.E. Local # 600 Eastern Region

Posted 02 February 2011 - 09:50 AM

You mean for the sake of not having to do any work? :-p


Even if you are working with an "available light situation," you get to chose what time of day you shoot. Do some research. If I were shooting with a DSLR I'd make damned sure the highlights didn't blow out; in the world of cinematography I am not alone. Better to underexposure the rest and pull it up later in correcting the footage than to blow out every single highlght and have no detail at all.

What's worse, noise or a complete lack of detail?
  • 0

#6 Adrian Sierkowski

Adrian Sierkowski
  • Sustaining Members
  • 7117 posts
  • Cinematographer
  • Los Angeles, Ca

Posted 02 February 2011 - 12:54 PM

But, I'll add it'll depend how much of the image is clipping, buy that I mean, I'd not get worked up over a small window in the back of a frame, unless it was becoming a distraction. I would, however, be concerned if the back of the frame was all window.. in which case you'd need to use fill light, unless you wanted silhouette.
There is no hard and fast "right and wrong" way to expose, there are ground rules of course, but they can't be applied super broadly.
  • 0

#7 Jed Shepherd

Jed Shepherd
  • Basic Members
  • PipPip
  • 60 posts
  • Student

Posted 02 February 2011 - 07:33 PM

You mean for the sake of not having to do any work? :-p


Even if you are working with an "available light situation," you get to chose what time of day you shoot. Do some research. If I were shooting with a DSLR I'd make damned sure the highlights didn't blow out; in the world of cinematography I am not alone. Better to underexposure the rest and pull it up later in correcting the footage than to blow out every single highlght and have no detail at all.

What's worse, noise or a complete lack of detail?

Thanks for the reply. I wasnt asking so i didnt have to do as much post work :) Your right in saying research the area but i just meant worse case. The reply after yours makes sense in saying not to worry if something small and not obvious is clipping but if its something big then its definitely a problem. But either way your answer was what i was thinking with the underexpose a little then bring the image back in post.
Thanks

Edited by Jed Shepherd, 02 February 2011 - 07:33 PM.

  • 0

#8 Devindra Sooknanan

Devindra Sooknanan
  • Basic Members
  • PipPip
  • 25 posts
  • Cinematographer
  • Bay area, california

Posted 03 February 2011 - 03:59 AM

hey joe, usually if i know i'm doing color correction later I'll use a flat setting for the camera then when exposing I'll point the to a highlight area and use the in camera meter. Then adjust the exposure so the highlights fall around +2 as the meter reads -2,-1,0,+1,+2 (with 0 being roughly 18% grey) this has worked well for me so far. Its kind of like using the the zebra's on a traditional video/hd cam. hope that helps. avoid blowing out as much as possible, unless you don't mind sky replacements :-)
  • 0

#9 Gabe Spangler

Gabe Spangler
  • Basic Members
  • PipPip
  • 34 posts
  • Other

Posted 11 February 2011 - 10:44 PM

Use Highlight Tone Priority. Other than that, it's like Hal said, it's called lighting. If you do end up with clipped whites, a Proc Amp filter in post at about a -0.5 will make them look less obnoxious.

Edited by Gabe Spangler, 11 February 2011 - 10:45 PM.

  • 0

#10 Arsen Avi Romanovich Bortnik

Arsen Avi Romanovich Bortnik

    New

  • Basic Members
  • Pip
  • 7 posts
  • Director
  • NJ / NYC

Posted 14 March 2011 - 12:48 AM

I own a 60D so im asking in regard to it but im sure the answer will apply to all of the canon dslr's. My question is about getting the best exposure out of the camera. Im wondering what would be the best option; letting highlights clip to some extent so that the rest of the image is exposed well or closing the iris to stop highlight clipping but darkening everything else. Im asking this as a kind of two part question. Im thinking in terms of color correction in post. By letting the highlights clip im losing the information for that section of the image but if i let them expose correclty then play with the shadows and midtones in post to brighten the areas which have become darker, would i get a reasonable image? I cant test this at the moment(macbook pro battery died) so im using a machine with no editing software.

I was thinking about this in terms of making it look like the camera has better dynamic range then it really does. Im using a low contrast picture style (not superflat, just low contrast, sharpness etc) so in theory i should get the most information within my shadows, so i was wondering if anyone had mucked around with getting really good exposure using a 3 way color corrector for example? Im sort of struggling to explain what i mean exactly but hopefully someone might be able to give me an answer and i can maybe build on my question from there.

Thanks

P.S. I know i could use a polarising filter to help with overexposed sky etc but im just refering to hot spots that appear within an evironment where a polarised filter wouldnt be ideal.


  • 0

#11 Arsen Avi Romanovich Bortnik

Arsen Avi Romanovich Bortnik

    New

  • Basic Members
  • Pip
  • 7 posts
  • Director
  • NJ / NYC

Posted 14 March 2011 - 01:13 AM

I hope some of this information can and will help you out, as far as color correcting with the 3 way in FCP, the best way to shoot that I have found is to primarily get it as close as you can to the proper exposure, I like underexposing my footage, maybe by a stop, than bumping up the whites, and lowering the blacks 2-3 increments or as you see it fit without degrading the footage,this will yield great contrast. I have a 5D Mark ii, and about to get a 7D as backup, as far as I am concerned with my experience using the 7D in the past, and all the post I have read, the footage from the 5D 7D 60D is very close to being of same quality, in respect to contrast it has been brought up by Professional Cinematographers that the 5D has a greater contrast than the 7D as well as the 5D, because the 5D has a bigger sensor it grabs more light. ironically it is because of the bigger sensor that there are moire patterns with these dslr's simply because of the real time down sampling of the footage. the 5D 7D 60D with their large sensors around 19MP yield a picture of around 5000 to 3000 pixels, vs the HD signal that is 1920x1080 pixels, so if this camera could handle the full picture spec of nearly 5000 x 3000 pixel output than you would have a similar Red Code 5K footage, maybe the 5D mark 5 for example would be able to handle that when these two technologies really merge together, but I can certainly guarantee these dslr's will be broken into reg versions to pro video versions, with a price range differential of anywhere from 3-5k if not more or less. I plan on using my 7D as B cam for alternate angles during dialogue or just as a B footage cam to bring with me rather than lugging around a 5D, I would not use this two cameras in low light conditions together as the 5D is better in low light, but at iso of 100 to 500 I would assume that I would get the same type of footage in regards to grain. As far as closing or opening the iris it depends from scene to scene, if you are filming talent with a medium shot for example you may want a shallow dof, blurring out the background, this solution is ideal not only in telling your story but as a workaround to the problems you amy encounter with moire problems, I am not sure you have any knowledge on ND filters but it is something you may want to think about purchasing, I have a ND 2-8 set which stops the iris down to a 5.6 helping you maintain your dof, thats why we use these cameras, for the dof besides the amazing skin tones and overall quality of the dslr's. Honestly the best way to see what you want out of your 60D is to hook it up to your laptop or desktop and check out the footage live. You can change all your camera functions, aperature, shutter, iso right there on your computer and get instant feedback. If you have not already checked out Shane Hulburt ASC, the primary advocate of the DSLR system, mainly the 5D, it is a must, and this guy knows what he is talking about...
check this out and you will feel as if your back in Toys R Us as a youth.. http://www.hurlbutvi...cinematography/ and check out the latest videos he is doing for B&H photo's priceless information http://www.hdslrhub.com/
If anybody is responding to this post thinks I have supplied some false info, or have a difference of opinion, please share, always good to have some inputs.

As far as slightly underexposing, this is not something I derived from my own experimenting, but rather from professional Cinematographers, of course you don't want to lose your highlights, or minor details, but for the sake of getting the best picture in your situation, do you really need to see the clear details of everything in the frame unless it is an object that is vital in telling your story?

Edited by Arsen Avi Romanovich Bortnik, 14 March 2011 - 01:18 AM.

  • 0


Media Blackout - Custom Cables and AKS

Opal

Willys Widgets

Gamma Ray Digital Inc

The Slider

Abel Cine

Broadcast Solutions Inc

Tai Audio

rebotnix Technologies

Rig Wheels Passport

Paralinx LLC

FJS International, LLC

CineLab

Metropolis Post

Visual Products

Wooden Camera

CineTape

Aerial Filmworks

Technodolly

Glidecam

Ritter Battery

CineTape

rebotnix Technologies

Media Blackout - Custom Cables and AKS

Willys Widgets

Technodolly

Broadcast Solutions Inc

Rig Wheels Passport

Gamma Ray Digital Inc

Paralinx LLC

Tai Audio

FJS International, LLC

Glidecam

CineLab

Abel Cine

Metropolis Post

Visual Products

The Slider

Aerial Filmworks

Ritter Battery

Opal

Wooden Camera